Engines that use alcohol fuel are difficult or impossible to start when the ambient temperature falls below about 10.degree. C. In many countries, the high domestic energy costs have forced consumers to switch to ethyl alcohol as an alternative fuel. This is particularly true in countries such as Brazil which have an abundance of sugar cane which is a renewable resource. Fuels such as ethanol have been recognized as suitable energy sources for combustion engines. Operational problems exist, however, and notable among such problems is the fact that ethanol has poor starting and driving characteristics when the ambient temperature is below about 10.degree. C. This results from the high latent heat of vaporization and the low vapor pressure of ethanol when compared with petroleum derived gasolines.
Many different approaches have been used to resolve the cold starting problems of ethanol fueled vehicles. Exemplary of the approaches has been to utilize an auxiliary tank for gasoline in which the gasoline would be used to start and warm up the vehicle. When the vehicle was warm, the fuel tanks would be switched and the alcohol fuel would be fed to the carburetor. Obviously, while the solution is viable, there are many difficulties encountered with using two fuel tanks with a vehicle.